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Year 2 LCRS Neurology > Sleep > Flashcards

Flashcards in Sleep Deck (23)
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1
Q

What are the bahavioral criteria for sleep?

A
  1. species specific posture
  2. minimal movement
  3. reduced sensitivity to outside stimmuli
  4. reversible to stimmulation
2
Q

Explain the EEG waves in different stages of sleep

A
  1. Awake–> fairly prominentn, small waves
  2. Stage 1+2–> Non-REM seep (light sleep)
    • slows down
  3. Stage 3+4–> Non-REM sleep, (deeper)
    • slow EEG reading waves
  4. REM Sleep (stage 5)
    • indistiguishable from awake EEG
3
Q

What is a EOG?

When is it used?

A

It is electro-oculography

–> used to senese eye movements in sleep

4
Q

Explain the changes in EOG waves in different stages of sleep

A
  • Awake
  • Stages 1+2 (light sleep)
    • decreased
  • Stages 3+4 (deep sleep)
    • decrease, but slow waves present
  • REM –> very very active, increased
5
Q

Explain the changes in EMG in different stages of sleep

A
  • Awake
    • rapid, a lot of muscle activity
  • Stage 1+2
    • decreased
  • Stage 3+4
    • decreased
  • REM
    • very much decreased
6
Q

How long is a typicall sleep cycle?

How does it look like?

A

Normally about 90min (get shorter over night)

  1. goes from awake via different stage to REM
  2. From REM goes up again to Stage 2
  3. From stage 2 (via 3+4 ) to REM
7
Q

How do HR and respiration change during sleep?

A

They both decrease during sleep, but increase again in REM sleep

8
Q

When do dreams occur?

A

They can occur in any stage of sleep, most likely in REM

9
Q

What are the characteristics of dreams?

What is their function?

A
  • Dreams are more emotional than awake–> higher activation of limbic system
  • Function not known yet but involved in
    • memory
    • disposal of unwanted memories?
    • savety valve for antisocial emotions?
10
Q

What is the RAS?

Where is it located?

A

Reticular activating system

It enables conciousness (not site of conciousness)

–> no concrete location known, but sits in brainstem and projects to different parts of the brain

11
Q

Which systems controll sleep?

A
  1. Lateral Hypothalamus
    • promotes wakefulness (orexin/hypocretin)
  2. Ventrolateral preoptic nucleus (anterior hypothalamus)
    • promotes sleep
  3. Suprachiasmatic nucleus
    • synchronises sleep with falling light level
12
Q

Explain the role of the lateral hypothalamus in the control of sleep

A

It promotes wakefullnes by stimmulating the RAS via orexins (neuropeptides) (american:hypocretin)

13
Q

Explain the role of the ventral hypothalamus in sleep controll

A

Ventral hypothalamus (ventral preoptic nucleus) promotes sleep by decreasing RAS activity

14
Q

Explain the role of the Suprachiasmatic nucleus in sleep regulation

A

It matches light levels with sleep

  • direct + indirect influence on RAS
  • stiummulates the pineal gland to produce melatonin (when dark)
  • Melatonin decreases RAS activity
15
Q

What are the results of sleep deprivation?

A

Sleep deprivation has crucial effects

  1. psychiatric (depression, stress, mood fluctuation, hallucinations etc.)
  2. neurological (impaired attention, memory, executive function)
  3. somatic (glucose intolerance, impaired immunity, increased apptite+ decreased leptin secretion, death)
16
Q

How does sleep regluation change after sleep deprivation?

A
  1. easier to fall asleep
  2. increase of slow wave sleep (NREM)
  3. Increase of REM sleep (after selective REM sleep deprivation)
17
Q

What is the function of sleep?

A

Not quite known yet

  • recovery?
  • energy saving?
  • specific brain function like memory consolidations etc?
18
Q

What is insomnia?

A

Regular problems sleeping

19
Q

Explain the prevalence, causes and treatment of insomnia

A
  • Very common, mostly transient
  • Can be due to
    • Physiological: sleep apnoea, chronic pain
    • brain dysfunction: depression, shift work fatal familial insomnia (rare)
  • Treatment:
    • sleep hygene
    • hypnotic drugs (enhave GABA)
    • sleep Cognitive behavioural therapy (CBT)
20
Q

What is sleep hygene?

Which factors are involved?

A
  • fixed times
  • routine
  • no late activity and meals
  • only go to bed when tired
  • don’t use bed for anything but sleeping
  • avoid caffein, nicotine, alcohol late at night
  • no napping during day

etc, etc,

21
Q

What is hypersomina?

Between which two types can you differentiate?

A

Increased sleepiness

  1. Primary cause
    • post-traumatic brain injury
    • narcrolepsy
    • ideopathic
  2. Secondary due to poor night sleep
    • Obstructive SA, noctural pain, anxiety, environmental factors (noise), neurodegenerative disease, medication
22
Q

How can you diagnose hypersomnia?

A

via the epworth sleepiness scale

–> rates likelyhood of falling asleep in different situations (subjective)

23
Q

What is narcrolepsy?

A
  • Repeatedly falling asleep during the day and impared night sleep
  • might be accompanied by sudden attacks with loss of muscle tone –> Cataplexy (often triggered by emotions)
  • possible mechanism: Orexin/hypocretin deficiency